Telecommunication systems for wireless or cellular communications often have an antenna, or an array of antenna elements, that emits and receives radio frequency (RF) signals to and from end user equipment (UEs). Complex circuits are used to provide electrical signals to the array of antenna elements so that the appropriate RF signals are radiated to a selected UE. For example, transmitter, power amplifier, hybrid, combiner, duplexer, filter and/or distribution network circuits may be used to radiate an RF signal from an antenna. Similarly, complex circuits may be used to convert a received RF signal to an electrical signal having UE information.
In cross-polarized antenna systems, such as for Long Term Evolution (LTE), an antenna is designed to emit two cross-polarized RF beams at +45° and −45° polarization respectively. Further, the two polarizations are set to the same down-tilt angle, for example 8°, for each of the two polarized beams. Other cross-polarized antennas system having adjustable tilt angles may provide versatile functionality for Multiple-Input and Multiple-Output (MIMO) or beamforming in general, such as versatile elevation or three-dimensional coverage.
Reducing the number of circuits used in a cross-polarized antenna system without affecting signal quality and reliability may significantly reduce the cost of manufacturing the system. Similarly, reducing the number of circuits used may reduce the time needed in testing and/or diagnosing an error in the antenna system. Also, reducing insertion loss caused by certain circuits may provide better antenna system performance and reliability.